This is an application for a 5-year renewal of an institutional training grant in the Epidemiology and Biostatistics of Aging, funded by NIA since 1996. This multidisciplinary program's goals are to train outstanding predoctoral and postdoctoral candidates to lead the next generation of quantitative research scientists addressing the health of our aging population. This program is conducted jointly by epidemiologists and biostatisticians with a strong commitment to bringing together students in both disciplines to develop expertise in the content areas and methodologies that are essential to advancement of the field. Students are trained to conduct leading- edge research that can inform the development of prevention programs to compress morbidity in the aging population. The program is based in the Departments of Epidemiology and Biostatistics but involves faculty from departments throughout our Schools of Public Health, Medicine, and Nursing. A Program Director in Biostatistics, Co-Director from Epidemiology, 6 other Associate Directors, and 28 other core faculty members will serve as mentors for the trainees. A core curriculum is expected of predoctoral trainees and customized to postdoctoral trainees. Trainees, half each from Epidemiology and Biostatistics, participate in biweekly research in progress meetings, seminars on aging, practica specific to this program, and training to build skills in multidisciplinary collaboration. Research experiences and mentors are selected to ensure high quality research worthy of peer-reviewed publication. We will continue to train students in epidemiologic and biostatistical method and their application to aging, with emphases on the epidemiology of chronic disease, disability and frailty, biostatistics and genetics research methods for gerontology, and the psychosocial epidemiology of late life, and, expand training on the design and conduct of clinical trials and add new emphases in comparative effectiveness and community-based participatory research. Trainees have been highly productive, gained substantial recognition for their research, and launched their careers in appealing positions with emphases on aging. Graduates will be effective leaders of multidisciplinary research teams tackling the health problems associated with the aging US population.